3/4 Ton Suburban Running Hot

Yesterday while waiting in line to pick up my daughter from school I noticed my water temp was steadily climbing.

Now here in the gulf coast of Texas it's hotter than a Mexican plate lunch this time of year. I don't remember exactly how hot it got but it was well over the 210° mark. I tested again today and it climbed up over 210° while idling for about 15 minutes but cooled down when I started driving again.

I plan to change the tstat and see if that helps. Fluid levels were fine and the pump doesn't appear to be leaking. May be time to upgrade to the 05+ electric fans.

PS. Where is the temp probe for the exterior temp that is in the rear view mirror loacted. While I was testing it today that readout said 130°[emoji91]

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Probably needs a fan clutch. Pretty common symptoms. E-fans are a nice upgrade if you can swing it. Clean truck!

I agree with the fan clutch. Pretty simple fix and cheap too.

Hmm to the parts house I go. Thanks.

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If you are good on fluids I would check the thermostat. If it's opening once the engine warms up then look at the water pump. If you rev the engine and the Temps drop chance are your pump is bad. I'd replace it after 100k miles and consider it a wear item. You temp probe is right in front of the radiator so it's catching some heat from the radiator getting too hot.. . U can see mine to the right of the trans cooler.

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All you have to do to confirm the engine fan clutch is take a rolled-up newspaper or magazine & stick it in the fan while the engine is idling; the fan will stop as there would be no torque from the clutch. Another way you can tell the clutch is out: the fan will still be spinning after you turn the engine off; a properly functioning unit will stop immediately after the engine is shut off.

Yep, fan. Also, backwash the radiator from the engine side.

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I changed the fan clutch. All is well now. Thanks for the advice.

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If you have the 8.1 like me, I suggest dropping in a 180 t stat. It will help with oil consumption and help run cooler. West Texas is pretty damn hot this time of year.b

I have the 6.0, would it still benefit from the 180 tstat? I still plan on doing the efan swap in the future.

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